time travel

[The 321 Anomaly]

I've been curious about time travel for a while now. Is it be possible? If so, how can it be done? I think that if one is able to manipulate the space-time continuum, that might be the way to do it, though I must admit I cannot began to imagine how someone is to go about doing such a thing. Another idea of mine is that if someone is able to externalize the reversal of a clock or wristwatch, then maybe it can be done. A while back, I read a little bit of Stephen Hawking's A Brief History of Time (the chapter about time travel) and I didn't understand a whole lot of it, but I've watched programs on the History channel that discuss theories regarding wormholes possibly causing those who enter them to enter a different time period.

[Astro Boy]

I've been curious about time travel for a while now. Is it be possible?

No it's not possible to travel in time since there is no future and no past just present and even the mathematical side of it it's will never be a reality since infinite amount of energy is required to accelerate something at the speed of light that will help to slow down time on traveller's side thus allowing him to technically travel in future since the rest of the universe will continue running at it's normal speed.

 

Time travel will stay in Holywood studios and in people imagination forever.

Edited July 15, 2011 by Astro Boy

[xxSilverPhinxx]

It's possible because of Einstein's Relativity to travel into the future. There are engineering impediments, however, because you would need to travel at very high speeds.

 

I'm not too sure about going to the past, though. If it were possible based on creating wormholes, it would have to be seen if wormholes big and stable enough could even be created. Not to mention there are all those paradoxes which don't have clear answers such as how someone can go back into the past and alter causes of the universe of which they themselves are an effect.

[IM Egdall]

People think of time travel as pure science fiction. But according to Einstein, it is something we experience in our everyday lives. It is just that the amount of time travel we undergo is so small we don't notice it. But it is real. This is not pseudo-science, but solidly grounded in Einstein's theories of relativity.

 

Per special relativity, time slows down with relative motion. This allows us to travel into the future. Again this is a tiny amount at the speeds we experience. If one day we develop a spaceship capable of speeds which are a significant fraction of the speed of light (which is about 670 million miles an hour), then this time travel effect would be appreciable.

 

 

Per general relativity, the rate at which time passes is affected by gravity. A lower clock runs slower compared to a higher clock. This means we can, in effect, travel into the future and into the past just by changing altitude. (But when we arrive back where we started, some time has always passed.) The effect here is also miniscule, because Earth's gravity is relatively weak.

 

See my blog posts under "Its Relative" for a detailed explanation.

(Edited for spelling and clarity.)

Edited July 15, 2011 by I ME

[Airbrush]

I've been curious about time travel for a while now. Is it be possible? If so, how can it be done? I think that if one is able to manipulate the space-time continuum, that might be the way to do it, though I must admit I cannot began to imagine how someone is to go about doing such a thing. Another idea of mine is that if someone is able to externalize the reversal of a clock or wristwatch, then maybe it can be done. A while back, I read a little bit of Stephen Hawking's A Brief History of Time (the chapter about time travel) and I didn't understand a whole lot of it, but I've watched programs on the History channel that discuss theories regarding wormholes possibly causing those who enter them to enter a different time period.

 

Suppose intelligent alien beings or probes have been visiting Earth for thousands of years, as the Ancient Aliens enthusiasts believe. How did they get here if they could not manupulate time passage? Probably their planet would be too far away to reach here without some kind of time compression.

 

If you consider the "Montauk Project" conspiracy theory (see Preston Nichols, Peter Moon, K. Wells), time travel would be here and now, but very secret, above top secret stuff. Anyone with the ability to time travel could easily go back in time and remove all evidence for time travel.

 

http://en.wikipedia.org/wiki/Montauk_Project

 

Most scientists don't believe significant time travel is possible for humans at this time and not in the near future, but what is possible thousands of years from now?

 

Wormholes are believed to be such extreme phenomena that humans could not survive passage through one. Passing through a wormhole is about as safe as jumping into a black hole.

Edited July 18, 2011 by Airbrush

[Ophiolite]

To answer the OP, time travel may be possible. Time travel, to the future or past, appears consistent with the mathematics of general relativity. Whether such a process would be practical, or whether the theoy would be borne out by further study is another matter.

 

Suppose intelligent alien beings or probes have been visiting Earth for thousands of years, as the Ancient Aliens enthusiasts believe. How did they get here if they could not manupulate time passage? Probably their planet would be too far away to reach here without some kind of time compression..

1. You have ignored the time compression that occurs as speeds approach that of light.

2. You have ignored the possibility of generation star ships.

3. You have ignore the possibility of suspended animation.

4. You have ignored the possibility of aliens with very long life spans.

[Marqq]

To answer the OP, time travel may be possible. Time travel, to the future or past, appears consistent with the mathematics of general relativity. Whether such a process would be practical, or whether the theoy would be borne out by further study is another matter.

 

I keep hearing this, along with ideas about wormholes and negative energies and all that, but I've never heard an explanation of how GR allows for time-travel into the past. I'm not sophisticated enough to go through the published theory and actually understand it, so could I ask you to put the essential portion of it into layman's terms?

[Ophiolite]

Regretably I am also a layman, but I am satisfied that the experts making these declarations are doing so within the constraints of well defined theory. (Though a layman, I pride myself on being able to spot bullshit from 6 parsecs away.)

 

As is often the case, Wikipedia is a good starting point and I offer these links, which I have found useful, as an introduction to the concepts.

http://en.wikipedia.org/wiki/Closed_timelike_curve

http://en.wikipedia.org/wiki/Timetravel

 

This is also a useful link, on Tipler cylinders:

http://www.andersoninstitute.com/tipler-cylinder.html

[Marqq]

Regretably I am also a layman, but I am satisfied that the experts making these declarations are doing so within the constraints of well defined theory. (Though a layman, I pride myself on being able to spot bullshit from 6 parsecs away.)

 

As is often the case, Wikipedia is a good starting point and I offer these links, which I have found useful, as an introduction to the concepts.

http://en.wikipedia...._timelike_curve

http://en.wikipedia....wiki/Timetravel

 

This is also a useful link, on Tipler cylinders:

http://www.andersoni...r-cylinder.html

 

I've checked the links, and I've gotta admit, I still don't get it.

In [acr=faster than light]FTL[/acr] information transmission, causality can apparently be violated by transmitting information among pairs of reference frames (2 stationary observers and 2 fast-moving observers). Something still doesn't ring true to me about this theory, and I attribute that to my limited understanding of special relativity. (In the visual aids in the link below, the moving pair's interaction is skewed in a way I don't understand.)

(ref http://www.theculture.org/rich/sharpblue/archives/000089.html )

There are a couple ideas very similar to this involving super-dense constructs spinning at great speeds used to (somehow) skew frames of reference to achieve the same result.

 

The other major mechanism involves the use of a wormhole (or system of wormholes), with one stationary end and one end that's moved to an area with greater inertial influence (forcing time-dilation) and then moved back to the same inertial environment of the stationary end. This sounds completely bogus to me, because time-dilation doesn't slow time, it inhibits the changes by which we measure the local perceived passage of time.

 

I think the only reason time-travel (to the past), or causality violation (love the new term I learned, ty ophiolite), are ideas still being entertained is due to misunderstandings and ambiguity in theories.

[Airbrush]

To answer the OP, time travel may be possible. Time travel, to the future or past, appears consistent with the mathematics of general relativity. Whether such a process would be practical, or whether the theoy would be borne out by further study is another matter.

 

Airbrush: "Suppose intelligent alien beings or probes have been visiting Earth for thousands of years, as the Ancient Aliens enthusiasts believe. How did they get here if they could not manupulate time passage? Probably their planet would be too far away to reach here without some kind of time compression.."

 

1. You have ignored the time compression that occurs as speeds approach that of light.

2. You have ignored the possibility of generation star ships.

3. You have ignore the possibility of suspended animation.

4. You have ignored the possibility of aliens with very long life spans.

 

Thanks for reinforcing your issue of how ignorant I am, as to how ETI's could get here. Repeating "you have ignored" 4 times is a good way to annoy anyone. I hinted at "some kind of time compression" which allows for other ways besides traveling near light speed. I had not thought of #2, 3, and 4, thanks for those, but I had #1 in mind when I made my post. Or #5 they send self-replicating Von Neumann probes.

 

Nice to know how good you are at detecting BS from parsecs away. I'm not so clairvoyant, and will rely on you for BS detection.

Edited July 19, 2011 by Airbrush

[Ophiolite]

Thanks for reinforcing your issue of how ignorant I am,

There is more knowledge in the world than any one person can know by several orders of magnitude. Therefore we are all hugely ignorant. I participate in forums such as this reduce my own ignorance and, if I can, help to reduce the ignorance of others. Perhaps you have other motives.

 

Repeating "you have ignored" 4 times is a good way to annoy anyone.

I apologise. I am truly sorry you are oversensitive. Would you prefer I had allowed you to remain ignorant? If so I can certainly oblige in future. (By the way if you had told me that I had ignored fifty things and each of your statements were accurate I should have welcomed your input, but if you want to use a different approach I'll try to respect it.)

 

Nice to know how good you are at detecting BS from parsecs away. I'm not so clairvoyant, and will rely on you for BS detection.

You are taking that statement out of context. Forty plus years in industry gives you an eye for bullshit.

[DrRocket]

The issue of time travel has been beat to death in several threads.

 

To repeat much of a post in one of them the situation is this:

 

General relativity by itself does not preclude closed timelike curves. But other things may, at least at the macroscopic level. This is Hawking's "Chronology Protection Conjecture".

 

Pretty much everyone expects that something like the chronology protection conjecture will be shown to be true. But it is not straightforward. Closed timelike curves do exist in some exotic solutions to the Einstein field equations. Gödel's lambda dust space, the Tipler cylinder and Kerr black holes have CTCs.

 

On the other hand Hawking showed that if the weak energy condition holds then there are no CTCs.

 

Quantum fields, as I understand it, generally do not conform to the weak energy condition (ajb chime in) so chronology protection may well not hold at the quantum level. There are Feynman diagrams that include non-causal branches.

 

There is good reason to demand a mathematical proof based on general relativity. Odd things really do happen. When black hole solutions were first found, many physicists, Einstein included, did not believe that physical black holes would exist. One learns in physics by pushing the limits of what is known and investigating situations that might be termed "exotic". Exotic is not necessarily impossible.

 

Any proof of the chronology protection conjecture will have to include some conditions that constrain the admissible solutions to the Einstein field equations. The known exotic solutions with CTCs serve to demonstrate that fact. General relativity alone is not enough.

 

In a sense the deep problem is that causality appears to not strictly hold at the quantum level, but it seems to apply in "normal" macroscopic situations. So, where is line between the quantum world and the macroscopic world where causality kicks in ? This is well worth understanding.

[Airbrush]

There is more knowledge in the world than any one person can know by several orders of magnitude. Therefore we are all hugely ignorant. I participate in forums such as this reduce my own ignorance and, if I can, help to reduce the ignorance of others. Perhaps you have other motives.

 

I apologise. I am truly sorry you are oversensitive. Would you prefer I had allowed you to remain ignorant? If so I can certainly oblige in future. (By the way if you had told me that I had ignored fifty things and each of your statements were accurate I should have welcomed your input, but if you want to use a different approach I'll try to respect it.)

 

You are taking that statement out of context. Forty plus years in industry gives you an eye for bullshit.

 

You are sorry I am oversensitive? Sure, OK, no problem friend. I appreciate your knowledge, which is far beyond my own. Just your manner is rough. If I was listing a number of things you were not apparently aware of, I would certainly not repeat the words "You are ignoring" over and over. I would simply list them after something easy-going like "You might consider...".

 

Forty years in Astronomy and Cosmology is awesome dude! Are you a science teacher? If so, you could be less condescending.

 

My Dad was a high school art teacher for 45 years (except 1942 - 1945 when he was in Army for WWII), until age 70.

 

Now let's get back to Astro & Cosmo.

 

Time travel and life after death are the two great human day dreams. Wanting them doesn't make them exist. But what if? So let's get busy and figure out how to do it.

Edited July 21, 2011 by Airbrush

[FutureBeast]

Regretably I am also a layman, but I am satisfied that the experts making these declarations are doing so within the constraints of well defined theory. (Though a layman, I pride myself on being able to spot bullshit from 6 parsecs away.)

 

As is often the case, Wikipedia is a good starting point and I offer these links, which I have found useful, as an introduction to the concepts.

http://en.wikipedia...._timelike_curve

http://en.wikipedia....wiki/Timetravel

 

This is also a useful link, on Tipler cylinders:

http://www.andersoni...r-cylinder.html

 

On this gentleman's website, Dr. David Lewis Anderson, he has claimed that he has produced machines called, "time generators," that produce closed time-like curves. He has also claimed that he and his group as well as other groups around the world are actively manipulating time on a significant level on a regular basis. This seems like laughable nonsense on it's face, but upon further inspection his credentials seem relatively believable which has left me in a rather precarious position.

 

Can anyone confirm that this is complete BS so I can go back to drinking coffee and reading the newspaper?

Edited October 16, 2011 by FutureBeast

[DrRocket]

On this gentleman's website, Dr. David Lewis Anderson, he has claimed that he has produced machines called, "time generators," that produce closed time-like curves. He has also claimed that he and his group as well as other groups around the world are actively manipulating time on a significant level on a regular basis. This seems like laughable nonsense on it's face, but upon further inspection his credentials seem relatively believable which has left me in a rather precarious position.

 

Can anyone confirm that this is complete BS so I can go back to drinking coffee and reading the newspaper?

 

It is BS and Anderson is a nut.

[Genius13]

what will this new discovery of the ''faster than light neutrino'' do to the relativity theory

[Ophiolite]

One of the following:

1. Nothing, because it will turn out to be a methodological error.

2. Nothing, since it will turn out that some neutrinos are tachyons.

3. Utter, complete, delightful chaos, leading to a radically improved understanding of what we think is reality.

[Aristarchus in Exile]

No it's not possible to travel in time since there is no future and no past just present and even the mathematical side of it it's will never be a reality since infinite amount of energy is required to accelerate something at the speed of light that will help to slow down time on traveller's side thus allowing him to technically travel in future since the rest of the universe will continue running at it's normal speed.

 

Time travel will stay in Holywood studios and in people imagination forever.

 

Absolutely correct! And man will never build heavier than air machines which will fly!

[DrRocket]

You are taking that statement out of context. Forty plus years in industry gives you an eye for bullshit.

 

Some people have 40 years of experience.

 

Some people have 1 year of experience 40 times.

[baric]

It is BS and Anderson is a nut.

 

It's funny. Anderson suggests building an impossible machine to accomplish an impossible task:

 

First take a piece of material 10 time the mass of the Sun, squeeze it together and roll it into a long, thin, super-dense cylinder – a bit like a black hole that has passed through a spaghetti factory. Then spin the cylinder up to a few billion revolutions per minute and see what happens.... For the mathematics to work properly, Tipler’s cylinder has to be infinitely long

 

It's almost like it was written by The Onion.

[FutureBeast]

Just to be fair, I don't believe that Dr. Anderson was suggesting building Tipler's Cylinder. It is a theoretical construct to examine a particular property of space time. He was suggesting he has already built the following machine:

 

http://andersoninsti...r-overview.html

 

Not making any claims of validity. I am merely keeping the argument on the relevant subject.

 

Ready, set, DEBUNK!

 

Another thought has occurred to me which is that since we are all time traveling to some extent all the time, though it is such a minuscule amount that we can't tell the difference, Is it possible that we are all violating the causality principle to some extent all the time however slight the violation? If neutrinos are moving faster than the speed of light and they are essentially arriving before they left what does that say for the human perception of time? If a satellite in space is moving a a different rate of time such that the clocks have to be adjusted in order to compensate for the loss of time on one end, what is actually happening temporally when an astronaut comes into contact with it in order to service the machine? Has he caused the satellite to instantly travel to his time frame? Has he traveled to it's time frame? Is that a causality violation? Will I eventually go crazy from this line of reasoning or reach nirvana?

Edited October 18, 2011 by FutureBeast

[36grit]

 

I love this subject. Go back in time and you'll be a child, forward and you'll be old. The only way I can think of to actually travel into the past (or future) like in the movies is to dream yourself there.

Ofcourse your physical body wont be able to follow you, but it might be possible to occupy and live in the one of your dream state.

 

 

 

 

 

[Aristarchus in Exile]

I don't know how anyone can say something is impossible since we don't know what is possible. That kind of attitude is what stunts the mind.

[baric]

I don't know how anyone can say something is impossible since we don't know what is possible. That kind of attitude is what stunts the mind.

 

 

The only material that could possibly maintain structural integrity in the form of an infinitely-long cylinder is unobtainium. And most likely, a particularly rare isotope of it designed for rigidity.

 

Good luck with that.

[Aristarchus in Exile]

The only material that could possibly maintain structural integrity in the form of an infinitely-long cylinder is unobtainium. And most likely, a particularly rare isotope of it designed for rigidity.

 

Good luck with that.

 

So we simply need to find a parallel universe with an infinite supply of unobtainium raria isotopia .. no big problem.

 

So we simply need to find a parallel universe with an infinite supply of unobtainium raria isotopia .. no big problem. But I think we can do without raria isotopia and go with common unobtainium by using anti-graity to float the cylinder.